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Spinal cord injury chronically alters cardiac structure and function and is associated with increased odds for cardiovascular disease. Here, we investigate the cardiac consequences of spinal cord injury on the acute-to-chronic continuum, and the contribution of altered bulbospinal sympathetic control to the decline in cardiac function following spinal cord injury. By combining experimental rat models of spinal cord injury with prospective clinical studies, we demonstrate that spinal cord injury causes a rapid and sustained reduction in left ventricular contractile function that precedes structural changes. In rodents, we experimentally demonstrate that this decline in left ventricular contractile function following spinal cord injury is underpinned by interrupted bulbospinal sympathetic control. In humans, we find that activation of the sympathetic circuitry below the level of spinal cord injury causes an immediate increase in systolic function. Our findings highlight the importance for early interventions to mitigate the cardiac functional decline following spinal cord injury.

Formation of an intramural left atrial hematoma (ILAH) is a rare complication of coronary artery stenting. Rapid diagnosis with noninvasive multimodality imaging can potentially be lifesaving. We report a case of ILAH that resulted in left ventricular inflow obstruction and pericardial tamponade in a 55-year-old male who presented with hemodynamic instability and worsening dyspnea three weeks after seemingly uncomplicated left circumflex artery stenting. We demonstrate features on transthoracic echocardiography with contrast and cardiac computed tomography that were used for diagnosis and management.

As part of an ongoing effort to better understand barriers to academic research, we reviewed and analyzed the process of research ethics applications, focusing on ethics approval time, within the Department of Medicine from 2006 to 2011. A total of 1,268 applications for approval to use human subjects in research were included in our analysis. Three variables, risk category (minimal vs. non-minimal risk), type of funding, and year of submission, were statistically significant for prediction of ethics approval time, with risk status being the most important of these. The covariate-adjusted mean time for approval for minimal risk studies (35.7 days) was less than half that of non-minimal risk protocols (76.5 days). Studies funded through a for-profit sponsor had significantly longer approval times than those funded through other means but were also predominantly (87%) non-minimal risk protocols. Further investigations of the reasons underlying the observed differences are needed to determine whether improved training for research ethics board (REB) members and/or greater dialogue with investigators may reduce the lengthy approval times associated with non-minimal risk protocols.

Aim Echocardiographic methods for estimating right atrial (RA) volume have not been standardized. Our aim was to evaluate two-dimensional (2D) echocardiographic methods of RA volume assessment, using RA volume by magnetic resonance imaging (MRI) as the reference. Methods and results Right atrial volume was assessed in 51 patients (mean age 63 ± 14 years, 33 female) who underwent comprehensive 2D echocardiography and cardiac MRI for clinically indicated reasons. Echocardiographic RA volume methods included (1) biplane area length, using four-chamber view twice (biplane 4C-4C); (2) biplane area length, using four-chamber and subcostal views (biplane 4C-subcostal); and (3) single plane Simpson's method of disks (Simpson's). Echocardiographic RA volumes as well as linear RA major and minor dimensions were compared to RA volume by MRI using correlation and Bland-Altman methods, and evaluated for inter-observer reproducibility and accuracy in discriminating RA enlargement. All echocardiography volumetric methods performed well compared to MRI, with Pearson's correlation of 0.98 and concordance correlation ≥0.91 for each. For bias and limits of agreement, biplane 4C-4C (bias -4.81 mL/m(2) , limits of agreement ±9.8 mL/m(2) ) and Simpson's (bias -5.15 mL/m(2) , limits of agreement ±10.1 mL/m(2) ) outperformed biplane 4C-subcostal (bias -8.36 mL/m(2) , limits of agreement ±12.5 mL/m(2) ). Accuracy for discriminating RA enlargement was higher for all volumetric methods than for linear measurements. Inter-observer variability was satisfactory across all methods. Conclusions Compared to MRI, biplane 4C-4C and single plane Simpson's are highly accurate and reproducible 2D echocardiography methods for estimating RA volume. Linear dimensions are inaccurate and should be abandoned.

The idea of nonsurgically entering the normal pericardial sac for diagnostic or therapeutic purposes was unrealistic until recently. This was largely due to the perception that access to the pericardial space by a pericardial puncture was only safely possible in the presence of a sizable pericardial effusion.

Pericardial effusion is defined as the accumulation of fluid in the pericardial space either as transudate (hydropericardium), exudate, pyopericardium or hemopericardium. Large pericardial effusions are most common with neoplastic, tuberculous, cholesterol, uremic pericarditis, myxedema, and parasitoses [1, 2]. Slowly developing pericardial effusions can be asymptomatic even when they are very 1–2 l large, while rapidly accumulating smaller effusions of 150–200 ml can cause fatal tamponade (Fig. 3.1). Loculated effusions occur after surgery, trauma, radiation and purulent infections. Effusions from a hydropericardium are usually small and occur mainly due to heart failure and fluid retention.

The management of hemodynamic instability caused by a growing pericardial effusion and cardiac tamponade requires the prompt evacuation of the effusion. This can be done either by pericardiocentesis or a surgical procedure. However, long-term prognosis of the patient and the risk for recurrences are not determined by the type of the initial procedure selected, but rather by the underlying etiology and the physician’s ability to treat the causal disease. Percutaneous balloon pericardiotomy is a palliative, alternative approach for the management of recurring pericardial effusion, applied so far mainly for recurrences of the neoplastic pericardial effusion [1]. The procedure is more complex than pericardiocentesis.

Percutaneous pericardioscopy is a diagnostic tool for the endoscopic visualization of lesions in both the epicardium and parietal pericardium. It enables safe and efficient targeted epicardial and parietal pericardial biopsy and provides the cardiologist with not only macroscopic but also microscopic evidence of pathologic changes [1].

Pericardiocentesis of moderate, small or loculated pericardial effusions is a controversial issue. It should not be routinely performed if the patient is not symptomatic and effusion is spontaneously resolving and unless further diagnostic and/or therapeutic options are available (e.g. pericardioscopy, epicardial or pericardial biopsy, application of intrapericardial treatment). In addition, access to the small or moderated effusions requires a learning curve. Several experimental and few clinical concepts have been developed for access of a small pericardial effusion or normal pericardium. These procedures will be reviewed in the following sections.

Due to the increased interest in the pericardial space for interventional procedures, and intrapericardial therapy the refined knowledge of its precise anatomy becomes more and more important [1–4]. Therefore, the aim of this chapter is to provide all necessary anatomic information for the operators performing pericardioscopy, pericardial/epicardial biopsies or epicardial ablation procedures.

The ability to access the normal pericardium in the absence of any effusion induced increasing interest in the pericardial space as a location of and novel approach for various cardiac and intrapericardial applications. Intrapericardial drug delivery may be superior to other routes in special indications. Medication applied intrapericardially will maintain the effective concentration for a longer time. Drugs given in the pericardial space may access the vessel wall and the myocardial tissue directly for a much longer time, but also more predictably and consistently than by an intracoronary or intravenous injection [1]. The intrapericardial route might have additional important advantages for the application of pharmacological agents like an easier access to perivascular tissue.

The application of pericardioscopy, targeted pericardial and epicardial biopsy as well as the analyses of the respective tissues, has certainly improved our understanding of the pathophysiology of the pericardial diseases. Most instruments used in the procedure such as endoscope, biopsy forceps and catheters were originally not designed for the application in the pericardium but for the use in other organs for endoscopic inspection or tissue acquisition. Informed consent of this circumstance from patient is recommended. Further progress has been achieved through the implementation of contemporary pathology (immunocytochemistry, immunohistochemistry) and molecular biology techniques (PCR to cardiotropic microbial agents) in the analysis of pericardial and epicardial biopsy samples.

During more than 200 years of practice of pericardial drainage in the history of medicine physicians had to select either an open surgical approach or blind pericardiocentesis, mainly according to the personal preferences and training. In the absence of valid imaging the open approach was safer regarding the risk of puncturing the cardiac chambers instead of the effusion, the second approach had the lower risk for secondary infection.

Independent of the etiology of the underlying disease the intrapericardial application of drugs offers the advantage that a high local dose can be applied with little systemic side effects. The pericardial sac is, similarly as the pleural space, a nearly ideal compartment for such an application with a very limited exchange of its content to the systemic circulation or other organs.

Pericardial effusion is the result of an increased production and/or decreased clearance of pericardial fluid. Samples of the fluid can be obtained for analyses by either needle pericardiocentesis, catheter drainage or surgical pericardiectomy. While laboratory analyses of pleural effusion are well established, the diagnostic approach to pericardial fluid is less clearly defined. An etiologically correct diagnosis of pericardial diseases can often be based on a positive fluid analysis alone but the sensitivity may vary between 24–93%, depending on the patient cohort and the diagnostic methods [1].

The data regarding the interrelationships of high-sensitive C-reactive protein (CRP), left atrial (LA) volume, and atrial fibrillation (AF) are sparse. Additionally, while LA volume has been shown to be useful for prediction of AF in low-to-moderate risk populations, its predictive value in clinically high-risk populations is unknown.SAFHIRE (Study of Atrial Fibrillation in High Risk Elderly) is an ongoing prospective study of the pathophysiology of first AF in persons agedor = 65 years withor = 2 other AF risk factors [systemic hypertension, proven coronary artery disease, heart failure (HF), diabetes]. Participants are followed annually, and undergo an interview, physical examination, blood work, electrocardiogram, and echocardiogram assessment.Of 800 participants, mean age of 74 +/- 6 years, 34 developed first AF over 1.7+/- 0.9 years. A history of systemic hypertension and proven coronary artery disease was present in 97% and 78%, respectively. CRP was unrelated to LA volume on univariable or multivariable analyses (P0.10), and not predictive of first AF on univariable or multivariable models (all P0.10). Indexed LA volume was an independent predictor of first AF (unadjusted P0.0001; age and sex adjusted P = 0.0006; adjusted for multiple factors, HR 1.3/5 ml per m(2), 95% CI, 1.09 to 1.48, P = 0.001).In this elderly population at high clinical risk for the development of first AF, CRP was unrelated to LA volume and nonpredictive of first AF, while indexed LA volume was incremental to clinical risk factors for the prediction of first AF.

A major advantage of echocardiography over other advanced imaging modalities (magnetic resonance imaging, computed tomographic angiography) is that echocardiography is mobile and real time. Echocardiograms can be recorded at the bedside, in the cardiac catheterization laboratory, in the cardiovascular intensive care unit, in the emergency room-indeed, any place that can accommodate a wheeled cart. This tremendous advantage allows for the performance of imaging immediately before, during, and after various procedures involving interventions. The purpose of this report is to review the use of echocardiography to guide interventions. We provide information on the selection of patients for interventions, monitoring during the performance of interventions, and assessing the effects of interventions after their completion. In this document, we address the use of echocardiography in commonly performed procedures: transatrial septal catheterization, pericardiocentesis, myocardial biopsy, percutaneous transvenous balloon valvuloplasty, catheter closure of atrial septal defects (ASDs) and patent foramen ovale (PFO), alcohol septal ablation for hypertrophic cardiomyopathy, and cardiac electrophysiology. A concluding section addresses interventions that are presently investigational but are likely to enter the realm of practice in the very near future: complex mitral valve repairs, left atrial appendage (LAA) occlusion devices, 3-dimensional (3D) echocardiographic guidance, and percutaneous aortic valve replacement. The use of echocardiography to select and guide cardiac resynchronization therapy has recently been addressed in a separate document published by the American Society of Echocardiography and is not further discussed in this document. The use of imaging techniques to guide even well-established procedures enhances the efficiency and safety of these procedures.

Left atrial (LA) structural and functional remodeling reflects a spectrum of pathophysiological changes that have occurred in response to specific stressors. These changes include alterations at the levels of ionic channels, cellular energy balance, neurohormonal expression, inflammatory response, and physiologic adaptations. There is convincing evidence demonstrating an important pathophysiological association between LA remodeling and atrial fibrillation (AF). Measures that will prevent, attenuate, or halt these processes of LA remodeling may have a major public health impact with respect to the epidemic of AF. In this review, we describe the mechanisms involved in LA remodeling and highlight the existing and potential therapeutic options for its reversal, and implications for AF development.

The purpose of this study was to assess the mortality trends of atrial fibrillation (AF) in a community.Limited data exist regarding the mortality trends of patients diagnosed with first AF.A community-based cohort of adult residents of Olmsted County, Minnesota, who had electrocardiogram-confirmed first-documented AF in the years 1980 to 2000 were identified and followed to 2004 or death. The primary outcome was all-cause mortality.Of a total of 4,618 residents (mean age 73 +/- 14 years) diagnosed with first AF, 3,085 died during a mean follow-up of 5.3 +/- 5.0 years. Relative to the age- and gender-matched general Minnesota population, the mortality risk was increased (p0.0001) with a hazard ratio (HR) of 9.62 (95% confidence interval [CI] 8.93 to 10.32) within the first 4 months and 1.66 (95% CI 1.59 to 1.73) thereafter. Cox proportional hazards modeling showed no change in overall age- and gender-adjusted mortality (HR for the year 2000 vs. 1980: 0.99; 95% CI 0.86 to 1.13; p = 0.84), even after adjustment for comorbidities. In secondary analyses, no changes in mortality were seen for early (within first 4 months) or late (after 4 months) mortality for the entire group or within the subgroup of patients who did not have cardiovascular disease at baseline.In this cohort of patients newly diagnosed with AF, mortality risk was high, especially within the first 4 months. There was no evidence for any significant changes over the 21 years in terms of overall mortality, early or late mortality, or mortality among patients without pre-existing cardiovascular disease.

This study sought to identify preoperative predictors of postoperative atrial fibrillation (POAF) among patients undergoing cardiac surgery.Postoperative atrial fibrillation is frequent after cardiac surgery and is associated with increased morbidity, mortality, prolonged hospital stay, and increased costs. Left atrial volume (LAV), a marker of chronically elevated left ventricular filling pressure, is a predictor of atrial fibrillation (AF) in the nonsurgical setting.A total of 205 patients (mean age 62 +/- 16 years; 35% women) undergoing cardiac surgery were prospectively enrolled. Clinical risk factors were obtained by detailed medical record review and patient interview. Preoperative transthoracic echocardiograms were performed for assessment of LAV, left ventricular ejection fraction, and diastolic function. Follow-up was complete. Detection of POAF was based on documentation of AF episodes by continuous telemetry throughout hospitalization.Postoperative atrial fibrillation occurred in 84 patients (41.4%) at a median of 1.8 days after cardiac surgery. The LAV was significantly larger in patients in whom AF developed (49 +/- 14 ml/m2 vs. 39 +/- 16 ml/m2, p = 0.0001). Patients with LAV32 ml/m2 had an almost five-fold increased risk of POAF, independently of age and clinical risk factors (adjusted hazard ratio 4.84, 95% confidence interval 1.93 to 12.17, p = 0.001). Age and LAV were the only independent predictors of POAF. The area under the receiver-operator characteristics curve to predict POAF was 0.729 for LAV and 0.768 for the combination of LAV and age (both p0.0001).The LAV is a strong and independent predictor of POAF. Risk stratification using LAV and age enables clinicians to identify high-risk patients before cardiac surgery.

Left atrial (LA) enlargement has been proposed as a barometer of diastolic burden and a predictor of common cardiovascular outcomes such as atrial fibrillation, stroke, congestive heart failure, and cardiovascular death. It has been shown that advancing age alone does not independently contribute to LA enlargement, and the impact of gender on LA volume can largely be accounted for by the differences in body surface area between men and women. Therefore, enlargement of the left atrium reflects remodeling associated with pathophysiologic processes. In this review, we discuss the normal size and phasic function of the left atrium. Further, we outline the clinically important aspects and pitfalls of evaluating LA size, and the methods for assessing LA function using echocardiography. Finally, we review the determinants of LA size and remodeling, and we describe the evidence regarding the prognostic value of LA size. The use of LA volume for risk stratification is an evolving science. More data are required with respect to the natural history of LA remodeling in disease, the degree of LA modifiability with therapy, and whether regression of LA size translates into improved cardiovascular outcomes.

We sought to compare left atrial (LA) volume to LA area and diameter for the prediction of adverse cardiovascular outcomes.The incremental value of LA volume compared with LA area or diameter as a cardiovascular risk marker has not been evaluated prospectively for patients with sinus rhythm or atrial fibrillation (AF).Left atrial size was assessed with biplane LA volume, four-chamber LA area, and M-mode dimension for 423 patients (mean age 71 +/- 8 years, 56% men) who were prospectively followed for development of first AF, congestive heart failure, stroke, transient ischemic attack, myocardial infarction, coronary revascularization, and cardiovascular death.Of the 317 subjects in sinus rhythm at baseline, 62 had 90 new events during a mean follow-up of 3.5 +/- 2.3 years. All three LA size parameters were independently predictive of combined outcomes (all p0.0001). The overall performance for the prediction of cardiovascular events was greatest for LA volume (area under the receiver operator characteristic curve: indexed LA volume 0.71; LA area 0.64; LA diameter 0.59). A graded association between the degree of LA enlargement and risk of cardiovascular events was only evident for indexed LA volume. For subjects with AF, there was no association between LA size and cardiovascular events.Left atrial volume is a more robust marker of cardiovascular events than LA area or diameter in subjects with sinus rhythm. The predictive utility of LA size for cardiovascular events in AF was poor, irrespective of the method of LA size quantitation.

We sought to test the hypothesis that C-reactive protein (CRP) can predict the recurrence of atrial fibrillation (AF) after successful electrical cardioversion (CV).In patients with AF, CRP levels are predictive of immediate failure of CV.We prospectively measured high-sensitivity CRP in 67 patients with AF or atrial flutter who underwent successful electrical CV.At one-month follow-up, 22 patients (33%) had recurrence of their arrhythmia. Arrhythmia recurrence was associated with significantly higher pre-CV CRP levels (odds ratio [OR] 1.84; 95% confidence interval [CI] 1.14 to 2.98; p = 0.013) even after adjusting for age (OR 2.22; 95% CI 1.25 to 3.93; p = 0.006), for gender (OR 1.89; 95% CI 1.16 to 3.09; p = 0.011), or duration of arrhythmia (OR 1.86; 95% CI 1.13 to 3.07; p = 0.015). On multivariate analysis, CRP was the only independent predictor of arrhythmia recurrence (OR 2.19; 95% CI 1.05 to 4.55; p = 0.036).Our data suggest that high levels of CRP are associated with an increased risk of recurrence of AF within one month. These data support the hypothesis that anti-inflammatory interventions may help in maintenance of normal sinus rhythm after CV. These data also may have implications for the identification of patients who are most likely to experience substantial benefit from CV therapy for AF.

We sought evidence of a change in the prevalence of atrial fibrillation (AF) over a 30-year period among residents of Rochester, Minnesota.Atrial fibrillation is increasingly encountered in clinical practice, but there is limited data on secular trends of AF over time.Within a longitudinal case-control study of ischemic stroke, the prevalence of AF and of selected comorbid conditions among incident stroke cases and age- and gender-matched controls between 1960 and 1989 was determined.The mean age +/- standard deviation for the 1,871 stroke cases (45% men) and matched controls was 75 +/- 11 years. For cases, age-adjusted estimates of AF prevalence for 1960 to 1969, 1970 to 1979, and 1980 to 1989 were 11%, 13%, and 16%, respectively, for men, and 13%, 16%, and 20% for women. For controls, the rates were 5%, 8%, and 12%, respectively, for men, and 4%, 6%, and 8% for women. Increasing AF prevalence was associated with increasing age (doubling of odds per decade of age in both cases and controls) and calendar time adjusted for age and gender (cases: odds ratio [OR] per 5 years 1.13, 95% confidence interval [CI], 1.05 to 1.22; controls: OR per 5 years 1.24, 95% CI 1.12 to 1.37). The rates of increase with calendar time were significant for cases (p = 0.001) and controls (p0.001) and comparable between the genders.The prevalence of AF increased significantly in ischemic stroke patients and their controls from 1960 to 1989 in Rochester, Minnesota, independent of age and gender. The rate of increase did not differ significantly between men and women.